圧縮変形におけるグリフィス軌跡
1976 年 92 巻 1060 号 p. 409-414
詳細
1976 年 92 巻 1060 号 p. 409-414
In this paper the compressive deformation of an elastic solid in which contains a penny-shaped crack is considered in order to explain the brittle fracture of rocks. The complete stress-strain curve derived here consists of a linear proportional part with effective Young's modulus and fracture locus or so-called Griffith locus. The cross point of the former and the later gives a starting point of crack dislocation which is determined from Griffith's criterion.
Griffith locus expressed in equations (24) or (28) corresponding respectively to uniaxial and triaxial compression shows following features.
(1) It is a continuous curve whose slope is positive in a part and is negative in other.
(2) It varies with confining pressure, while depends on intrinsic physical constants of solid and geometric parameters of crack.
(3) If the initial crack size is smaller than a critical value, given in equation (29) in uniaxial compression, the elastic body may sustrain unstable fracture.
